The purpose of this study is to examine the efficacy of exercise in comparison to wellness education to determine if they can improve the effects of prolonged exposure therapy (PE) in reducing symptoms of anxiety associated with Post-traumatic Stress Disorder (PTSD). In addition, the two strategies (i.e., exercise and wellness education) will be compared in terms of improvements in sleep as well as levels of brain-derived neurotrophic factor (BDNF). BDNF is a protein that helps to support the survival of existing neurons and stimulate the growth new neurons and synapses. BDNF is important to learning and memory in general and therefore may be associated with the learning and memory as it relates to PE and corresponding symptom PTSD improvement.